The proposed research examines the learning and memory functions of limbic brain circuitry involving the hippocampus, retrosplenial cortex, and the anterior and lateral dorsal thalamus. Pathology in these regions has been associated with the human cognitive impairments seen in amnesic syndromes and Alzheimer's disease. The specific goal is to examine the contributions these regions make to contextual learning. It is proposed that these regions function cooperatively to encode the cognitive and behavioral features of a learning context and thereby provide a basis for determining appropriate behaviors in different learning situations. To assess this, multi-site neuronal recording and temporary inactivation techniques will be employed while rats learn to obtain food rewards in two different learning contexts.